TSP

　　This solid is called triple superphosphate. Residual HF typically reacts with silicate minerals co-mingled with the phophate ores to produce hydrofluorosilicic acid (H2SiF6). The majority of the hexafluorosilicic acid is converted to aluminium fluoride and cryolite for the processing of aluminium. These materials are central to the conversion of aluminium ore into aluminium metal.

　　When sulfuric acid is used, the product contains phosphogypsum ( CaSO4·2H2O) and is called single superphosphate.